The compact Model 70S was designed as a rear effects speaker in surround sound applications, but could also be used as a main speaker in a dedicated sub-sat system, in particular with the matching 40B subwoofer. Using the same Uni-Q array as in the Model 90 centre speaker, uniform coverage over the listening area was assured, as was the timbre match with Reference Series main speakers.

Reference Series Model 40B (1993-98)

Designed specifically to partner the 70S satellite speaker, but more than capable in a home theatre system based around any of the KEF Reference Series loudspeakers, Model 40B used the same twin coupled cavity bass loading technique employed for the top models in the range. Model 40B helped to strengthen the home theatre capability of the KEF loudspeaker range at a time when the market was growing rapidly and demanding quality products. For two-channel or multi-channel, the 40B gave the KEF customer increased flexibility in creating the optimum home audio system.